61518643200 has 684 divisors, whose sum is σ = 253545193200. Its totient is φ = 13967032320.

The previous prime is 61518643181. The next prime is 61518643211. The reversal of 61518643200 is 234681516.

It is a happy number.

61518643200 is a `hidden beast` number, since 6 + 1 + 5 + 1 + 8 + 643 + 2 + 0 + 0 = 666.

It is a super-2 number, since 2×61518643200² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 412876726 + ... + 412876874.

Almost surely, 2^61518643200 is an apocalyptic number.

61518643200 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61518643200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (126772596600).

61518643200 is an abundant number, since it is smaller than the sum of its proper divisors (192026550000).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61518643200 is an equidigital number, since it uses as much as digits as its factorization.

61518643200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208 (or 166 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The spelling of 61518643200 in words is "sixty-one billion, five hundred eighteen million, six hundred forty-three thousand, two hundred".